Erceg helicopter's site calculated by pilot, computer

The wreckage was found by a search team using information provided by Westpac Rescue Helicopter pilot Darryl Sherwin.

He had spent hours privately putting radar data into a computer program and passed on the results last Tuesday.

Mr Sherwin said it took "some convincing people to listen to me ... but finally somebody did and when they did they went out and found it". Mr Sherwin had been involved in the official search on November 9 and the Westpac chopper spent five hours searching a 500m area round Mt Karioi.

He returned to Auckland with a "gut feeling" and asked the national rescue centre for its radar track of the Westpac helicopter during the search.

When it came through, he noticed the radar track did not correspond to his map and GPS co-ordinates.

Mr Sherwin was given copies of Mr Erceg's helicopter radar track and put the data, including the helicopter's direction and air speed, into a computer program. "I came up with the theory that the aircraft was still another 693m to the east of ... where it was last seen on the radar."